本研究分別探討摻雜過渡金屬釕Ru的La0.7Sr0.3Mn0.9Ru0.1O3(LSMRO)和未摻雜的鑭鍶錳氧La0.7Sr0.3MnO3（ LSMO）的異質結構在磁性條紋調控和偏置耦合效應 Exchaged Bias）上的表現差異。LSMO因其豐富的磁性和電子組態使其在磁性材料研究中具有重要地位（是現現熱門研研究的材料之 （。摻入Ru元素後是將使LSMO的自旋軌道耦合 SOC）增強是預期會對其磁性質產生顯著影響。
通過施加不同大小與方向的磁場及電流來操控異質結構中的磁性條紋是並比較在不同參雜條件下的偏置耦合效應。其中我們利用自由支撐技術(Freestanding, FS)是以減少基板引起的應變效應是從而獲得更真實的磁性質是這項技術經常運用在開發高性能的磁性記憶元件與高靈活性的電子元件。實驗方法包括使用脈衝雷射沉積(Pulsed Laser Deposition)製備高品質的薄膜、自由支撐技術的應用以及針對整體磁性的測量(VSM, XMCD)和量測表面磁性條紋的掃描探針顯微鏡(SPM)。
研究結果顯示是摻入Ru後的LSMO薄膜在磁性條紋調控上表現出更大的穩定性。然而（是在未摻入Ru的LSMO中展示了較強的偏置耦合效應是這結果顯示出LSMO與Ru所增強的自旋軌道耦合時會產生自旋受挫(Spin frustration)。這些發現不僅提供了關於磁性材料設計和應用的新見解是還為新穎的元件開發提供了理論支持和實驗依據。

In the past decades, Lanthanum strontium manganite (La1-xSrxMnO3, LSMO) has been a well-known material because of their unique physical properties and potential of revealing interesting new phenomena. In this work, we investigated the properties of LSMO and its Ru-doped variant, LSMRO, with particular emphasis on the modulation of magnetic textures and exchange bias (EB) inherent in their heterostructures. The high quality thin films have been fabricated successfully via Pulsed Laser Deposition (PLD). Our work focused on the influence of Ruthenium doping, geometrical limitations, and the application of external magnetic fields on the regulation of magnetic domains, employing Magnetic Force Microscopy (MFM) and Photoemission Electron Microscopy (PEEM).Furthermore, we investigated the effects of Ruthenium (Ru) doping and freestanding techniques on the exchange bias (EB) strength through the application of Vibrating Sample Magnetometry (VSM) and X-ray Magnetic Circular Dichroism (XMCD).
Our research demonstrates that the incorporation of Ru doping significantly augments Spin-Orbit Coupling (SOC), resulting in the stabilization of magnetic domains; however, it concurrently induces spin frustration, thereby diminishing the exchange bias (EB) strength. This investigation offers valuable perspectives on the magnetic characteristics of LSMRO from various analytical viewpoints.

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